/* =============================================================================
 * M02_DF_InputPanel_Vars.ts
 * 입력 상자 판 — 변수(그룹 밖 정보: 면적 · 길이 · 부피 …) 정의: 이름 · 갈래(숫자 / 선택 / 글) · 단위 · 범위 · 예시값
 * 변수마다 출력 알약 하나 · `M02_DF_InputPanel.ts` 가 부름 · 글 [한, 영] 짝은 아래
 * ========================================================================== */

import { currentLanguageIndex } from "@ui/ui_template_locale";
import { createButton, createInputField, createSelectField, el } from "@ui/ui_template_elements";
import type { CfLogic, CfVariable } from "./M02_DF_Model";
import { checkVariable, putVariable, removeVariable } from "./M02_DF_InputPanel_Build";

const TEXT = {
  List: ["변수 — 알약마다 하나", "Variables — one pill each"],
  None: ["아직 변수가 없음 — 아래에서 만듦", "No variable yet"],
  Name: ["이름", "Name"],
  Type: ["갈래", "Type"],
  Number: ["숫자", "Number"],
  Choice: ["선택", "Choice"],
  Text: ["글", "Text"],
  Unit: ["단위", "Unit"],
  Min: ["범위 아래", "Range from"],
  Max: ["범위 위", "Range to"],
  Choices: ["선택 목록(쉼표로 나눔)", "Choices (comma separated)"],
  Example: ["예시값", "Example"],
  Add: ["변수 넣기", "Add variable"],
  Save: ["고치기 끝", "Save change"],
  Edit: ["고치기", "Edit"],
  Remove: ["삭제", "Remove"],
  Cancel: ["취소", "Cancel"],
  Line: ["{n} · {u} · 예시 {e}", "{n} · {u} · e.g. {e}"],
  Range: ["범위 {a}~{b}", "range {a}~{b}"],
} as const;

type TKey = keyof typeof TEXT;
const t = (key: TKey, v: Record<string, string | number> = {}): string =>
  Object.entries(v).reduce(
    (s, [k, x]) => s.replace(`{${k}}`, String(x)),
    TEXT[key][currentLanguageIndex] as string,
  );

const numOf = (s: string): number | null =>
  s.trim() !== "" && Number.isFinite(Number(s)) ? Number(s) : null;

/** 변수 한 줄 글 */
export function variableLine(v: CfVariable): string {
  const base = t("Line", {
    n: v.name,
    u: v.unit || "-",
    e: v.example === null ? "—" : String(v.example),
  });
  const range =
    v.type === "number" && v.range ? ` · ${t("Range", { a: v.range[0], b: v.range[1] })}` : "";
  const choices = v.type === "choice" ? ` · ${(v.choices ?? []).join(" / ")}` : "";
  return `${base}${range}${choices}`;
}

export function renderVariables(
  host: HTMLElement,
  lg: CfLogic,
  boxId: string,
  on: { change(lg: CfLogic): void },
): void {
  const box = lg.boxes.find((b) => b.id === boxId);
  const vars = box?.input?.variables ?? [];
  let editing: CfVariable | null = null;

  const form = (): HTMLElement => {
    const cur = editing;
    const name = createInputField({
      type: "text",
      label: t("Name"),
      value: cur?.name ?? "",
      placeholder: "예: 면적",
      compact: true,
    });
    const type = createSelectField({
      label: t("Type"),
      options: [
        { value: "number", text: t("Number") },
        { value: "choice", text: t("Choice") },
        { value: "text", text: t("Text") },
      ],
      value: cur?.type ?? "number",
      compact: true,
      onChange: () => paint(),
    });
    const unit = createInputField({
      type: "text",
      label: t("Unit"),
      value: cur?.unit ?? "",
      placeholder: "예: ㎡",
      compact: true,
    });
    const lo = createInputField({
      type: "text",
      label: t("Min"),
      value: cur?.range ? String(cur.range[0]) : "",
      compact: true,
    });
    const hi = createInputField({
      type: "text",
      label: t("Max"),
      value: cur?.range ? String(cur.range[1]) : "",
      compact: true,
    });
    const choices = createInputField({
      type: "text",
      label: t("Choices"),
      value: (cur?.choices ?? []).join(", "),
      compact: true,
    });
    const example = createInputField({
      type: "text",
      label: t("Example"),
      value: cur?.example === null || cur?.example === undefined ? "" : String(cur.example),
      compact: true,
    });
    const extra = el("div", { className: "m02-dfip__stack" });
    const paint = (): void => {
      const ty = type.select.value;
      extra.replaceChildren(
        ...(ty === "number" ? [lo.root, hi.root] : ty === "choice" ? [choices.root] : []),
      );
    };
    paint();
    const submit = (): void => {
      const ty = type.select.value as CfVariable["type"];
      const ex = example.input.value.trim();
      const v: CfVariable = {
        name: name.input.value.trim(),
        type: ty,
        unit: unit.input.value.trim(),
        example: ex === "" ? null : ty === "number" ? (numOf(ex) ?? ex) : ex,
        ...(ty === "number" && numOf(lo.input.value) !== null && numOf(hi.input.value) !== null
          ? { range: [Number(lo.input.value), Number(hi.input.value)] as [number, number] }
          : {}),
        ...(ty === "choice"
          ? {
              choices: choices.input.value
                .split(",")
                .map((s) => s.trim())
                .filter(Boolean),
            }
          : {}),
      };
      const why = checkVariable(
        v,
        vars.filter((x) => x.name !== cur?.name),
      );
      name.setError(why ?? undefined);
      if (why) return;
      on.change(putVariable(lg, boxId, v, cur?.name));
    };
    const ok = createButton({ label: cur ? t("Save") : t("Add"), onClick: submit });
    const cancel = cur
      ? createButton({
          label: t("Cancel"),
          variant: "ghost",
          onClick: () => ((editing = null), draw()),
        })
      : null;
    return el("div", {
      className: "m02-dfip__form",
      children: [
        name.root,
        type.root,
        unit.root,
        extra,
        example.root,
        el("div", { className: "m02-dfip__chips", children: cancel ? [ok, cancel] : [ok] }),
      ],
    });
  };

  const draw = (): void => {
    const list = vars.length
      ? vars.map((v) =>
          el("div", {
            className: "m02-dfip__item",
            children: [
              el("span", { text: variableLine(v) }),
              createButton({
                label: t("Edit"),
                variant: "ghost",
                size: "sm",
                onClick: () => ((editing = v), draw()),
              }),
              createButton({
                label: t("Remove"),
                variant: "ghost",
                size: "sm",
                onClick: () => on.change(removeVariable(lg, boxId, v.name)),
              }),
            ],
          }),
        )
      : [el("p", { className: "m02-dfip__muted", text: t("None") })];
    host.replaceChildren(el("h5", { text: t("List") }), ...list, form());
  };
  draw();
}